Light source device

Abstract

The invention discloses light source devices applied in backlight modules of image display panels. The light source device includes a current source unit generating a driving current, a plurality of light emitting units coupled in series to the current source unit, a plurality of current shunts corresponding to the light emitting units respectively and providing current bypasses for the driving current to bypass the corresponding light emitting units, a plurality of light sensing units sensing the brightness of the light emitting units, and a control unit generating a plurality of current shunt control signals for separately controlling the current shunts. Each of the current shunt control signals is generated according to the sensed brightness of the corresponding light emitting unit and is used in controlling the conduction statement of the current bypass provided by the corresponding current shunt.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to light source devices and particularly relates to light source devices applied in backlight modules.[0003]2. Description of the Related Art[0004]The backlight module adopted in liquid crystal display (LCD) normally comprises a light source device implemented by a light emitting element array. The light emitting element array is composed of a plurality of light emitting elements. FIG. 1 illustrates a conventional light emitting element array. In this case, it is a 4×4 light emitting elements array. Each column of the light emitting element array includes a plurality of light emitting elements (LEDs) coupled in series. The LEDs of the same column share a single driving current I.[0005]The drawback of the conventional light emitting element array shown in FIG. 1 is that the brightness of each of the LEDs cannot be controlled separately. Referring to FIG. 1, the LEDs of the same column share ...

AI Technical Summary

Benefits of technology

[0007]One embodiment of the invention provides light source devices applied in backlight modules of image display panels. The light source device includes a current source unit generating a driving current, a plurality of light emitting units, a plurality of current shunts, a plurality of light sensing units and a control unit. The light emitting units are coupled in series to the current source unit. Each of the current shunts is corresponding to one of the light emitting units and provides a current bypass for the driving current to bypass the corresponding light emitting unit. Each

Problems solved by technology

The drawback of the conventional light emitting element array shown in FIG. 1 is that the brightness of each of the LEDs cannot be controlled separately.

However, the electronic characteristics of the LEDs may be different because of manufacture process deviation.

Moreover, when any LED malfunctions, the other LEDs of the same column stop illuminating because the current path of the driving current I is blocked by the malfunctioned LED.

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